Mercury derivative of dibrom-fluorescein



w I Patented 1 2 J umrun. STATES PATENT OFFICE.

EDWIN c. WHITE, or BALTIMORE, MARYLAND.

MERCURY. DERIVATIVE or DIBROM-FLUORESCEIN.

No Drawing. Application filed July 26, 1921, Serial No. 487,686. Renewed January 5,1925.

To aZZ whom it mmycomem: Be it known thatrI, EDWIN C.'WHI:rE, a citizen of the United States, residing at Baltimore, in the State of Maryland, have 5 invented certain new and useful Improvements in Mercury Derivatives of Dibrom- Fluorescein, of which the following is a specification.

This invention relates to a novel them peutic agent,- comprising essentially the mono-mercury derivative of di-brom-fluorescein, or an alkali-metal salt of such derivative, and to the process of preparing the same. For a full understanding of the inven- 3 tion I will describe in detail a preferred mode of practicing the same, it being under stood however that the invention is not restricted to the precise conditions specified by way of example. I

49 grams of di-brom fluorescein are dissolved ina solution' of 8 grams of sodium hydroxid in 50 c. c. of water, and diluted to 200 c.c. To this solution 12.5 c. c. of glacial acetic acid are added with stirring. With sufliciently vigorous stirring a homogeneous pastry precipitate results.

A filtered solution of about 22.5 grams of mercuric oxid in 25 c. c. of glacial acetic an acid and 50 c. c. of water, diluted after solution to -100 c. c., is then added to the suspended precipitate, and the whole diluted to about 500 c. c. The mixture is boiled until a small portion of filtered solution 5 gives no test for mercury when treated with ammonium sulfid, the approximate time required for this operation being about 4.5-6

hours. As the boiling continues the pre cipitate becomes darker in. color and more 40 granular. It is washed, preferably by centrifuging, to remove acetic acid and sodium acetate, and dried at about 110 C. B close adherence to these conditions an a most quantitative yield may be secured.

l The quantity of mercuric oxid specified above is in slight excess of the mono-molecular equivalent (21.7 grams): this excess. takes care of the loss as mercurous acetate,

other local infections.

which is always formed in small proportion when commercial yellow oxid of mercury is dissolved in acetic acid.

The product may be regarded as consistinn' essentially of di-brom-hydroxymercur v fluorescein, resulting from the substantially complete hydrolysis of an acetoxy-mercury compound which is probably formed as an intermediate. It is a red powder, which when ground exhibits marked dielectric properties, adhering to glass or paper even when perfectly dry. It is insoluble in the lents of sodium hydroxid yielding a deep cherry-red. solution." Although the solution is stable it is regarded'as a desirable precaution to keep it in dark colored bottles to decrease the tendency to decomposition on long standing.

.The new preparation is employed either in 'the form of the free acid or its soluble (usually sodium) salts. The latter are readily prepared, for example by dissolving the red powder in an amount of sodium hy droxid solution sufficient to form the disodium salt, and evaporating'the' solution to dryness at as'low a temperature as practicable, preferably under reduced pressure. The preparations are useful locally in the treatment of genito-urinary infections and I claim 1. The herein described novel product having. therapeutic properties com rising the chlorine-free mono-mercury derivative of di-brom-fluorescein.

2. The herein described novel products having them eutic proper-ties comprising the chlorineee alkali'metal salts of the mono-mercury derivative of di-brom-fluorescein.

. 3. Process of preparing a mercury derivative of di-brom-fluorescein comprising reacting with mercuric acetate on an aqueous suspension of di-brom-fluorescein. In testimony whereof, I affix my signature.

EDWIN 0. WHITE.

so usual solvents but dissolves in two eqnivav 

